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1.
Nature ; 627(8003): 281-285, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38286342

RESUMEN

Tight relationships exist in the local Universe between the central stellar properties of galaxies and the mass of their supermassive black hole (SMBH)1-3. These suggest that galaxies and black holes co-evolve, with the main regulation mechanism being energetic feedback from accretion onto the black hole during its quasar phase4-6. A crucial question is how the relationship between black holes and galaxies evolves with time; a key epoch to examine this relationship is at the peaks of star formation and black hole growth 8-12 billion years ago (redshifts 1-3)7. Here we report a dynamical measurement of the mass of the black hole in a luminous quasar at a redshift of 2, with a look back in time of 11 billion years, by spatially resolving the broad-line region (BLR). We detect a 40-µas (0.31-pc) spatial offset between the red and blue photocentres of the Hα line that traces the velocity gradient of a rotating BLR. The flux and differential phase spectra are well reproduced by a thick, moderately inclined disk of gas clouds within the sphere of influence of a central black hole with a mass of 3.2 × 108 solar masses. Molecular gas data reveal a dynamical mass for the host galaxy of 6 × 1011 solar masses, which indicates an undermassive black hole accreting at a super-Eddington rate. This suggests a host galaxy that grew faster than the SMBH, indicating a delay between galaxy and black hole formation for some systems.

2.
Mol Cell ; 82(20): 3826-3839.e9, 2022 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-36113481

RESUMEN

Ribosomal RNAs (rRNAs) are the most abundant cellular RNAs, and their synthesis from rDNA repeats by RNA polymerase I accounts for the bulk of all transcription. Despite substantial variation in rRNA transcription rates across cell types, little is known about cell-type-specific factors that bind rDNA and regulate rRNA transcription to meet tissue-specific needs. Using hematopoiesis as a model system, we mapped about 2,200 ChIP-seq datasets for 250 transcription factors (TFs) and chromatin proteins to human and mouse rDNA and identified robust binding of multiple TF families to canonical TF motifs on rDNA. Using a 47S-FISH-Flow assay developed for nascent rRNA quantification, we demonstrated that targeted degradation of C/EBP alpha (CEBPA), a critical hematopoietic TF with conserved rDNA binding, caused rapid reduction in rRNA transcription due to reduced RNA Pol I occupancy. Our work identifies numerous potential rRNA regulators and provides a template for dissection of TF roles in rRNA transcription.


Asunto(s)
ARN Polimerasa I , Factores de Transcripción , Humanos , Ratones , Animales , ARN Polimerasa I/genética , ARN Polimerasa I/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , ARN Ribosómico/genética , Transcripción Genética , ADN Ribosómico/genética , ARN , Cromatina
3.
Artículo en Inglés | MEDLINE | ID: mdl-38502541

RESUMEN

RATIONALE: Respiratory syncytial virus (RSV) is a common global respiratory virus increasingly recognized as a major pathogen in frail older adults and as a cause of chronic obstructive pulmonary disease (COPD) exacerbations. There is no single test for RSV in adults with acceptable diagnostic accuracy. Trials of RSV vaccines have recently shown excellent safety and efficacy against RSV in older adults; defining the frequency of RSV-related community infections and COPD exacerbations is important for vaccine deployment decisions. OBJECTIVES: This prospective study aimed to establish the frequency of outpatient-managed RSV-related exacerbations of COPD in two well-characterized patient cohorts using a combination of diagnostic methods. METHODS: Participants were recruited at specialist clinics in London, UK and Groningen, NL from 2017 and observed for three consecutive RSV seasons, during exacerbations and at least twice yearly. RSV infections were detected by reverse transcription-polymerase chain reaction (RT-PCR) and serologic testing. MEASUREMENTS AND MAIN RESULTS: 377 patients with COPD attended 1,999 clinic visits and reported 310 exacerbations. There were 27 RSV-related exacerbations (8·7% of total); of these, seven were detected only on PCR, 16 only on serology and 4 by both methods. Increases in RSV specific N-protein antibody were as sensitive as antibody to pre-F or post-F for serodiagnosis of RSV related exacerbations. CONCLUSIONS: RSV is associated with 8.7% of outpatient managed COPD exacerbations in this study. Antibodies to RSV-N protein may have diagnostic value, potentially important in a vaccinated population. The introduction of vaccines that prevent RSV is expected to benefit patients with COPD. This article is open access and distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).

4.
J Mol Cell Cardiol ; 174: 47-55, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36410526

RESUMEN

Mitochondrial permeability transition pore (mPTP)-dependent cell death is a form of necrotic cell death that is driven by mitochondrial dysfunction by the opening of the mPTP and is triggered by increases in matrix levels of Ca2+ and reactive oxygen species. This form of cell death has been implicated in ischemic injuries of the heart and brain as well as numerous degenerative diseases in the brain and skeletal muscle. This review focuses on the molecular triggers and regulators of mPTP-dependent necrosis in the context of myocardial ischemia reperfusion injury. Research over the past 50 years has led to the identity of regulators and putative pore-forming components of the mPTP. Finally, downstream consequences of activation of the mPTP as well as ongoing questions and areas of research are discussed. These questions pose a particular interest as targeting the mPTP could potentially represent an efficacious therapeutic strategy to reduce infarct size following an ischemic event.


Asunto(s)
Poro de Transición de la Permeabilidad Mitocondrial , Daño por Reperfusión Miocárdica , Humanos , Poro de Transición de la Permeabilidad Mitocondrial/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Necrosis/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Muerte Celular , Mitocondrias Cardíacas/metabolismo
5.
Am J Respir Crit Care Med ; 204(9): 1075-1085, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34319857

RESUMEN

Rationale: Chronic obstructive pulmonary disease (COPD) is a condition punctuated by acute exacerbations commonly triggered by viral and/or bacterial infection. Early identification of exacerbation triggers is important to guide appropriate therapy, but currently available tests are slow and imprecise. Volatile organic compounds (VOCs) can be detected in exhaled breath and have the potential to be rapid tissue-specific biomarkers of infection etiology. Objectives: To determine whether volatile organic compound measurement could distinguish viral from bacterial infection in COPD. Methods: We used serial sampling within in vitro and in vivo studies to elucidate the dynamic changes that occur in VOC production during acute respiratory viral infection. Highly sensitive gas chromatography-mass spectrometry techniques were used to measure VOC production from infected airway epithelial-cell cultures and in exhaled breath samples from healthy subjects experimentally challenged with rhinovirus (RV)-A16 and from subjects with COPD with naturally occurring exacerbations. Measurements and Main Results: We identified a novel VOC signature comprising decane and other long-chain alkane compounds that is induced during RV infection of cultured airway epithelial cells and is also increased in the exhaled breath from healthy subjects experimentally challenged with RV and from patients with COPD during naturally occurring viral exacerbations. These compounds correlated with the magnitude of antiviral immune responses, viral burden, and exacerbation severity but were not induced by bacterial infection, suggesting that they represent a specific virus-inducible signature. Conclusions: Our study highlights the potential for measurement of exhaled breath VOCs as rapid, noninvasive biomarkers of viral infection. Further studies are needed to determine whether measurement of these signatures could be used to guide more targeted therapy with antibiotic/antiviral agents for COPD exacerbations.


Asunto(s)
Biomarcadores/análisis , Pruebas Respiratorias/métodos , Diagnóstico Precoz , Infecciones por Picornaviridae/diagnóstico , Infecciones por Picornaviridae/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Compuestos Orgánicos Volátiles/análisis , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
6.
Am J Respir Crit Care Med ; 202(4): 549-557, 2020 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-32267724

RESUMEN

Rationale: Chronic obstructive pulmonary disease (COPD) exacerbations are prone to nonrecovery, but there are no data about the effectiveness of retreatment for these prolonged events. We examined whether further therapy with ciprofloxacin for incompletely resolved COPD exacerbations prolonged the time until the next event.Objectives: To assess whether incompletely recovered COPD exacerbations benefit from additional treatment with ciprofloxacin, at Day 14.Methods: In a multicenter, randomized double-blind placebo-controlled trial, we studied retreatment with oral ciprofloxacin 500 mg or matched placebo twice daily for 7 days in patients with Global Initiative for Chronic Obstructive Lung Disease stage II-IV COPD and persistent symptoms and/or serum C-reactive protein ≥8 mg/L initiated 14 (±3) days after an index COPD exacerbation. The primary outcome was the time to the next exacerbation within a 90-day period.Measurements and Main Results: Among 826 patients screened at four centers, 144 eligible participants with incomplete recovery were randomized to receive ciprofloxacin (n = 72) or placebo (n = 72). Within 90 days of randomization, 57% of the patients in the ciprofloxacin group and 53% in the placebo group experienced one or more exacerbations. The median time to the next exacerbation was 32.5 days (interquartile range 13-50) in the placebo arm and 34 days (interquartile range 17-62) in the ciprofloxacin arm, which was not significantly different (adjusted hazard ratio, 1.07; 95% confidence interval, 0.68-1.68; P = 0.76). No significant differences were seen in quality-of-life scores or lung function between the treatment groups.Conclusions: In patients with persistent symptoms and/or raised C-reactive protein 14 days after a COPD exacerbation, an additional course of ciprofloxacin resulted in no additional benefit compared with placebo. This suggests that nonrecovered exacerbations are not driven by ongoing bacterial infection and may potentially be targeted with antiinflammatory therapy.Clinical trial registered with www.clinicaltrials.gov (NCT02300220).


Asunto(s)
Ciprofloxacina/uso terapéutico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Anciano , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Retratamiento , Factores de Tiempo , Resultado del Tratamiento
7.
J Infect Dis ; 222(Suppl 7): S584-S591, 2020 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-32227102

RESUMEN

BACKGROUND: Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis in young infants. However, it is also a significant pathogen in older adults. Validated biomarkers of RSV disease severity would benefit diagnostics, treatment decisions, and prophylactic interventions. This review summarizes knowledge of biomarkers for RSV disease in adults. METHODS: A literature review was performed using Ovid Medline, Embase, Global health, Scopus, and Web of Science for articles published 1946-October 2016. Nine articles were identified plus 9 from other sources. RESULTS: From observational studies of natural infection and challenge studies in volunteers, biomarkers of RSV susceptibility or disease severity in adults were: (1) lower anti-RSV neutralizing antibodies, where neutralizing antibody (and local IgA) may be a correlate of susceptibility/severity; (2) RSV-specific CD8+ T cells in bronchoalveolar lavage fluid preinfection (subjects with higher levels had less severe illness); and (3) elevated interleukin-6 (IL-6), IL-8, and myeloperoxidase levels in the airway are indicative of severe infection. CONCLUSIONS: Factors determining susceptibility to and severity of RSV disease in adults have not been well defined. Respiratory mucosal antibodies and CD8+ T cells appear to contribute to preventing infection and modulation of disease severity. Studies of RSV pathogenesis in at-risk populations are needed.


Asunto(s)
Biomarcadores/sangre , Infecciones por Virus Sincitial Respiratorio/diagnóstico , Infecciones por Virus Sincitial Respiratorio/inmunología , Índice de Severidad de la Enfermedad , Anticuerpos Neutralizantes/inmunología , Bronquiolitis , Linfocitos T CD8-positivos/inmunología , Humanos , Inmunidad Celular , Inflamación , Interleucina-6 , Interleucina-8 , Infecciones por Virus Sincitial Respiratorio/virología , Virus Sincitial Respiratorio Humano/inmunología , Carga Viral
8.
Phys Rev Lett ; 122(10): 101102, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30932663

RESUMEN

During its orbit around the four million solar mass black hole Sagittarius A* the star S2 experiences significant changes in gravitational potential. We use this change of potential to test one part of the Einstein equivalence principle: the local position invariance (LPI). We study the dependency of different atomic transitions on the gravitational potential to give an upper limit on violations of the LPI. This is done by separately measuring the redshift from hydrogen and helium absorption lines in the stellar spectrum during its closest approach to the black hole. For this measurement we use radial velocity data from 2015 to 2018 and combine it with the gravitational potential at the position of S2, which is calculated from the precisely known orbit of S2 around the black hole. This results in a limit on a violation of the LPI of |ß_{He}-ß_{H}|=(2.4±5.1)×10^{-2}. The variation in potential that we probe with this measurement is six magnitudes larger than possible for measurements on Earth, and a factor of 10 larger than in experiments using white dwarfs. We are therefore testing the LPI in a regime where it has not been tested before.

9.
BMC Pregnancy Childbirth ; 18(1): 421, 2018 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-30359228

RESUMEN

BACKGROUND: Although exempt, many pregnant Muslim women partake in the daily fast during daylight hours during the month of Ramadan. In other contexts an impoverished diet during pregnancy impacts on birth weight. The aim of this systematic review was to determine whether Ramadan fasting by pregnant women affects perinatal outcomes. Primary outcomes investigated were perinatal mortality, preterm birth and small for gestational age (SGA) infants. Secondary outcomes investigated were stillbirth, neonatal death, maternal death, hypertensive disorders of pregnancy, gestational diabetes, congenital abnormalities, serious neonatal morbidity, birth weight, preterm birth and placental weight. METHODS: Systematic review and meta-analysis of observational studies and randomised controlled trials was conducted in EMBASE, MEDLINE, CINAHL, Web of Science, Google Scholar, the Health Management Information Consortium and Applied Social Sciences Index and Abstracts. Studies from any year were eligible. Studies reporting predefined perinatal outcomes in pregnancies exposed to Ramadan fasting were included. Cohort studies with no comparator group or that considered fasting outside pregnancy were excluded, as were studies assuming fasting practice based solely upon family name. Quality of included studies was assessed using the ROBINS-I tool for assessing risk of bias in non-randomised studies. Analyses were performed in STATA. RESULTS: From 375 records, 22 studies of 31,374 pregnancies were included, of which 18,920 pregnancies were exposed to Ramadan fasting. Birth weight was reported in 21 studies and was not affected by maternal fasting (standardised mean difference [SMD] 0.03, 95% CI 0.00 to 0.05). Placental weight was significantly lower in fasting mothers (SMD -0.94, 95% CI -0.97 to -0.90), although this observation was dominated by a single large study. No data were presented for perinatal mortality. Ramadan fasting had no effect on preterm delivery (odds ratio 0.99, 95% CI 0.72 to 1.37) based on 5600 pregnancies (1193 exposed to Ramadan fasting). CONCLUSIONS: Ramadan fasting does not adversely affect birth weight although there is insufficient evidence regarding potential effects on other perinatal outcomes. Further studies are needed to accurately determine whether Ramadan fasting is associated with adverse maternal or neonatal outcome.


Asunto(s)
Ayuno/fisiología , Resultado del Embarazo/epidemiología , Peso al Nacer/fisiología , Femenino , Humanos , Recién Nacido , Islamismo , Mortalidad Perinatal , Embarazo
11.
Pharm Res ; 32(2): 714-22, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25193129

RESUMEN

PURPOSE: Use isothermal microcalorimetry to directly evaluate the effects of excipients and water content to produce a stable amorphous glycopyrrolate pressurized metered dose inhaler (pMDI) formulation. METHODS: Amorphous glycopyrrolate particles with and without excipients (Distearoyl-sn-glycero-3-phosphatidylcholine (DSPC) or ß-cyclodextrin (ßCD)) were spray dried and cold filled along with HFA 134a into customized thermal activity monitor (TAM) measurement ampoules. When applicable, a known amount of water was also pipetted into the ampoule. Sample ampoules were hermetically sealed, equilibrated to 25°C and measured isothermally for at least 24 h using the TAM III (TA Instruments, Sollentuna, Sweden). RESULTS: Amorphous glycopyrrolate particles were highly unstable and crystallized rapidly when suspended in HFA 134a. Co-spray drying the glycopyrrolate with DSPC failed to mitigate this instability, but co-spray drying with ßCD protected the amorphous glycopyrrolate from crystallization, resulting in a stable formulation at low water contents (≤ 100 ppm). CONCLUSIONS: This study shows that isothermal microcalorimetry can easily differentiate between physically stable and unstable pMDI formulations of glycopyrrolate within a few hours. Furthermore, it allows rapid screening of various formulation factors (drug form, excipients, water ingress), which can greatly reduce the time required to develop marketable products with acceptable shelf life.


Asunto(s)
Calorimetría/métodos , Excipientes/química , Glicopirrolato/química , Temperatura , Agua/química , Excipientes/análisis , Glicopirrolato/análisis , Agua/análisis
12.
J Appl Microbiol ; 119(1): 11-24, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25865951

RESUMEN

Ethanol production directly from CO2 , utilizing genetically engineered photosynthetic cyanobacteria as a biocatalyst, offers significant potential as a renewable and sustainable source of biofuel. Despite the current absence of a commercially successful production system, significant resources have been deployed to realize this goal. Utilizing the pyruvate decarboxylase from Zymomonas species, metabolically derived pyruvate can be converted to ethanol. This review of both peer-reviewed and patent literature focuses on the genetic modifications utilized for metabolic engineering and the resultant effect on ethanol yield. Gene dosage, induced expression and cassette optimizat-ion have been analyzed to optimize production, with production rates of 0·1-0·5 g L(-1) day(-1) being achieved. The current 'toolbox' of molecular manipulations and future directions focusing on applicability, addressing the primary challenges facing commercialization of cyanobacterial technologies are discussed.


Asunto(s)
Cianobacterias/metabolismo , Etanol/metabolismo , Procesos Autotróficos , Biocombustibles/microbiología , Cianobacterias/genética , Microbiología Industrial , Fotosíntesis
13.
Pharm Res ; 31(10): 2716-23, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24760449

RESUMEN

PURPOSE: The techniques available to study formulation stability in pressurized metered dose inhalers (pMDIs) are limited, due to the challenging conditions of working with high pressure propellants. Isothermal microcalorimetry is a valuable tool used to screen and aid in formulation development of solid and solution drug formulations; however there are currently no available methods to evaluate pMDIs. In this paper, we have developed a method that allows measurement of such pressurized systems. METHODS: Samples were prepared by cold filling ampoules with propellant (HFA 134a) and drugs of interest. Ampoule caps were fitted with a specific O-ring, coated with paraffin and pre-conditioned prior to measurement. Samples were equilibrated at 25°C, placed in a Thermal Activity Monitor III (TAM III) system and measured isothermally at 25°C for a period of at least 24 h. RESULTS: Using well-defined procedures and ampoule preparation techniques we were able to safely contain the volatile propellant and acquire a stable measurement baseline. We were able to rapidly determine, within 6 h, the physical stability of amorphous and crystalline drug forms of beclomethasone dipropionate and formoterol fumarate dihydrate when formulated with HFA 134a. CONCLUSIONS: Isothermal microcalorimetry in pressurized HFA propellant systems was shown to be a rapid screening tool to evaluate pMDI formulation physical stability. This method can potentially be applied to study pMDI formulation factors to expedite product development.


Asunto(s)
Propelentes de Aerosoles/química , Beclometasona/química , Calorimetría/métodos , Etanolaminas/química , Hidrocarburos Fluorados/química , Inhaladores de Dosis Medida/normas , Beclometasona/administración & dosificación , Cristalización , Estabilidad de Medicamentos , Diseño de Equipo , Etanolaminas/administración & dosificación , Fumarato de Formoterol , Microscopía Electrónica de Rastreo , Propiedades de Superficie
14.
Int J Gynaecol Obstet ; 165(2): 579-585, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38064233

RESUMEN

Maternal reports of decreased fetal movement (DFM) are a common reason to present to maternity care and are associated with stillbirth and other adverse outcomes. Promoting awareness of fetal movements and prompt assessment of DFM has been recommended to reduce stillbirths. However, evidence to guide clinical management of such presentations is limited. Educational approaches to increasing awareness of fetal movements in pregnant women and maternity care providers with the aim of reducing stillbirths have recently been evaluated in a several large clinical trials internationally. The International Stillbirth Alliance Virtual Conference in Sydney 2021 provided an opportunity for international experts in fetal movements to share reports on the findings of fetal movement awareness trials, consider evidence for biological mechanisms linking DFM and fetal death, appraise approaches to clinical assessment of DFM, and highlight research priorities in this area. Following this workshop summaries of the sessions prepared by the authors provide an overview of understandings of fetal movements in maternity care at the current time and highlights future directions in fetal movement research.


Asunto(s)
Servicios de Salud Materna , Mortinato , Embarazo , Femenino , Humanos , Movimiento Fetal , Mujeres Embarazadas , Escolaridad
15.
Cells ; 13(2)2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38247800

RESUMEN

High-protein diets (HPDs) offer health benefits, such as weight management and improved metabolic profiles. The effects of HPD on cardiac arrhythmogenesis remain unclear. Atrial fibrillation (AF), the most common arrhythmia, is associated with inflammasome activation. The role of the Absent-in-Melanoma 2 (AIM2) inflammasome in AF pathogenesis remains unexplored. In this study, we discovered that HPD increased susceptibility to AF. To demonstrate the involvement of AIM2 signaling in the pathogenesis of HPD-induced AF, wildtype (WT) and Aim2-/- mice were fed normal-chow (NC) and HPD, respectively. Four weeks later, inflammasome activity was upregulated in the atria of WT-HPD mice, but not in the Aim2-/--HPD mice. The increased AF vulnerability in WT-HPD mice was associated with abnormal sarcoplasmic reticulum (SR) Ca2+-release events in atrial myocytes. HPD increased the cytoplasmic double-strand (ds) DNA level, causing AIM2 activation. Genetic inhibition of AIM2 in Aim2-/- mice reduced susceptibility to AF, cytoplasmic dsDNA level, mitochondrial ROS production, and abnormal SR Ca2+-release in atrial myocytes. These data suggest that HPD creates a substrate conducive to AF development by activating the AIM2-inflammasome, which is associated with mitochondrial oxidative stress along with proarrhythmic SR Ca2+-release. Our data imply that targeting the AIM2 inflammasome might constitute a novel anti-AF strategy in certain patient subpopulations.


Asunto(s)
Fibrilación Atrial , Dieta Rica en Proteínas , Animales , Ratones , Fibrilación Atrial/etiología , Fibrilación Atrial/metabolismo , Citoplasma , Dieta Rica en Proteínas/efectos adversos , Proteínas de Unión al ADN/metabolismo , Inflamasomas
16.
Sci Adv ; 10(31): eadj3145, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093977

RESUMEN

Mutation in nucleophosmin (NPM1) causes relocalization of this normally nucleolar protein to the cytoplasm (NPM1c+). Despite NPM1 mutation being the most common driver mutation in cytogenetically normal adult acute myeloid leukemia (AML), the mechanisms of NPM1c+-induced leukemogenesis remain unclear. Caspase-2 is a proapoptotic protein activated by NPM1 in the nucleolus. Here, we show that caspase-2 is also activated by NPM1c+ in the cytoplasm and DNA damage-induced apoptosis is caspase-2 dependent in NPM1c+ but not in NPM1wt AML cells. Strikingly, in NPM1c+ cells, caspase-2 loss results in profound cell cycle arrest, differentiation, and down-regulation of stem cell pathways that regulate pluripotency including impairment of the AKT/mTORC1 pathways, and inhibition of Rictor cleavage. In contrast, there were minimal differences in proliferation, differentiation, or the transcriptional profile of NPM1wt cells lacking caspase-2. Our results show that caspase-2 is essential for proliferation and self-renewal of AML cells expressing mutated NPM1. This study demonstrates that caspase-2 is a major effector of NPM1c+ function.


Asunto(s)
Apoptosis , Caspasa 2 , Proliferación Celular , Leucemia Mieloide Aguda , Mutación , Proteínas Nucleares , Nucleofosmina , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Leucemia Mieloide Aguda/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Caspasa 2/metabolismo , Caspasa 2/genética , Humanos , Animales , Diferenciación Celular , Línea Celular Tumoral , Autorrenovación de las Células/genética , Ratones , Daño del ADN
17.
Am J Obstet Gynecol MFM ; 5(3): 100821, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36481411

RESUMEN

OBJECTIVE: Reduced fetal movement, defined as a decrease in the frequency or strength of fetal movements as perceived by the mother, is a common reason for presentation to maternity care. Observational studies have demonstrated an association between reduced fetal movement and stillbirth and fetal growth restriction related to placental insufficiency. However, individual intervention studies have described varying results. This systematic review and meta-analysis aimed to determine whether interventions aimed at encouraging awareness of reduced fetal movement and/or improving its subsequent clinical management reduce the frequency of stillbirth or other important secondary outcomes. DATA SOURCES: Searches were conducted in MEDLINE, Embase, CINAHL, The Cochrane Library, Web of Science, and Google Scholar. Guidelines, trial registries, and gray literature were also searched. Databases were searched from inception to January 20, 2022. STUDY ELIGIBILITY CRITERIA: Randomized controlled trials and controlled nonrandomized studies were eligible if they assessed interventions aimed at encouraging awareness of fetal movement or fetal movement counting and/or improving the subsequent clinical management of reduced fetal movement. Eligible populations were singleton pregnancies after 24 completed weeks of gestation. The primary review outcome was stillbirth; a number of secondary maternal and neonatal outcomes were specified in the review. METHODS: Risk of bias was assessed using the Cochrane Risk of Bias 2 and Risk of Bias in Non-Randomized Studies I tools for randomized controlled trials and nonrandomized studies, respectively. Variation caused by heterogeneity was assessed using I2. Data from studies employing similar interventions were combined using random effects meta-analysis. RESULTS: A total of 1609 citations were identified; 190 full-text articles were evaluated against the inclusion criteria, 18 studies (16 randomized controlled trials and 2 nonrandomized studies) were included. The evidence is uncertain about the effect of encouraging awareness of fetal movement on stillbirth when compared with standard care (2 studies, n=330,084) with a pooled adjusted odds ratio of 1.19 (95% confidence interval, 0.96-1.47). Interventions for encouraging awareness of fetal movement may be associated with a reduction in neonatal intensive care unit admissions and Apgar scores of <7 at 5 minutes of age and may not be associated with increases in cesarean deliveries or induction of labor. The evidence is uncertain about the effect of encouraging fetal movement counting on stillbirth when compared with standard care with a pooled odds ratio of 0.69 (95% confidence interval, 0.18-2.65) based on data from 3 randomized controlled trials (n=70,584). Counting fetal movements may increase maternal-fetal attachment and decrease anxiety when compared with standard care. When comparing combined interventions of fetal movement awareness and subsequent clinical management with standard care (1 study, n=393,857), the evidence is uncertain about the effect on stillbirth (adjusted odds ratio, 0.86; 95% confidence interval, 0.70-1.05). CONCLUSION: The effect of interventions for encouraging awareness of reduced fetal movement alone or in combination with subsequent clinical management on stillbirth is uncertain. Encouraging awareness of fetal movement may be associated with reduced adverse neonatal outcomes without an increase in interventions in labor. The meta-analysis was hampered by variations in interventions, outcome reporting, and definitions. Individual studies are frequently underpowered to detect a reduction in severe, rare outcomes and no studies were included from high-burden settings. Studies from such settings are needed to determine whether interventions can reduce stillbirth.


Asunto(s)
Trabajo de Parto , Servicios de Salud Materna , Recién Nacido , Embarazo , Femenino , Humanos , Mortinato , Movimiento Fetal , Placenta
18.
bioRxiv ; 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37398413

RESUMEN

Mutation in nucleophosmin (NPM1) causes relocalization of this normally nucleolar protein to the cytoplasm ( NPM1c+ ). Despite NPM1 mutation being the most common driver mutation in cytogenetically normal adult acute myeloid leukemia (AML), the mechanisms of NPM1c+-induced leukemogenesis remain unclear. Caspase-2 is a pro-apoptotic protein activated by NPM1 in the nucleolus. Here, we show that caspase-2 is also activated by NPM1c+ in the cytoplasm, and DNA damage-induced apoptosis is caspase-2-dependent in NPM1c+ AML but not in NPM1wt cells. Strikingly, in NPM1c+ cells, loss of caspase-2 results in profound cell cycle arrest, differentiation, and down-regulation of stem cell pathways that regulate pluripotency including impairment in the AKT/mTORC1 and Wnt signaling pathways. In contrast, there were minimal differences in proliferation, differentiation, or the transcriptional profile of NPM1wt cells with and without caspase-2. Together, these results show that caspase-2 is essential for proliferation and self-renewal of AML cells that have mutated NPM1. This study demonstrates that caspase-2 is a major effector of NPM1c+ function and may even be a druggable target to treat NPM1c+ AML and prevent relapse.

19.
Lancet Respir Med ; 11(5): 415-424, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36528039

RESUMEN

BACKGROUND: COVID-19 has overwhelmed health services globally. Oral antiviral therapies are licensed worldwide, but indications and efficacy rates vary. We aimed to evaluate the safety and efficacy of oral favipiravir in patients hospitalised with COVID-19. METHODS: We conducted a multicentre, open-label, randomised controlled trial of oral favipiravir in adult patients who were newly admitted to hospital with proven or suspected COVID-19 across five sites in the UK (n=2), Brazil (n=2) and Mexico (n=1). Using a permuted block design, eligible and consenting participants were randomly assigned (1:1) to receive oral favipiravir (1800 mg twice daily for 1 day; 800 mg twice daily for 9 days) plus standard care, or standard care alone. All caregivers and patients were aware of allocation and those analysing data were aware of the treatment groups. The prespecified primary outcome was the time from randomisation to recovery, censored at 28 days, which was assessed using an intention-to-treat approach. Post-hoc analyses were used to assess the efficacy of favipiravir in patients aged younger than 60 years, and in patients aged 60 years and older. The trial was registered with clinicaltrials.gov, NCT04373733. FINDINGS: Between May 5, 2020 and May 26, 2021, we assessed 503 patients for eligibility, of whom 499 were randomly assigned to favipiravir and standard care (n=251) or standard care alone (n=248). There was no significant difference between those who received favipiravir and standard care, relative to those who received standard care alone in time to recovery in the overall study population (hazard ratio [HR] 1·06 [95% CI 0·89-1·27]; n=499; p=0·52). Post-hoc analyses showed a faster rate of recovery in patients younger than 60 years who received favipiravir and standard care versus those who had standard care alone (HR 1·35 [1·06-1·72]; n=247; p=0·01). 36 serious adverse events were observed in 27 (11%) of 251 patients administered favipiravir and standard care, and 33 events were observed in 27 (11%) of 248 patients receiving standard care alone, with infectious, respiratory, and cardiovascular events being the most numerous. There was no significant between-group difference in serious adverse events per patient (p=0·87). INTERPRETATION: Favipiravir does not improve clinical outcomes in all patients admitted to hospital with COVID-19, however, patients younger than 60 years might have a beneficial clinical response. The indiscriminate use of favipiravir globally should be cautioned, and further high-quality studies of antiviral agents, and their potential treatment combinations, are warranted in COVID-19. FUNDING: LifeArc and CW+.


Asunto(s)
COVID-19 , Adulto , Humanos , Persona de Mediana Edad , Anciano , SARS-CoV-2 , Resultado del Tratamiento , Pirazinas/uso terapéutico
20.
Curr Pain Headache Rep ; 16(3): 278-86, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22447132

RESUMEN

This article explores possible relationships between migraine, irritable bowel syndrome (IBS), celiac disease (CD), and gluten sensitivity. These seemingly distinct medical entities curiously share many common epidemiological, psychosocial, and pathophysiological similarities. Considerable evidence is emerging to support a concept that experiencing significant threatening adverse events creates a state of hypervigilance in the nervous system, which associates with exaggerated response to future threats and episodic attacks of migraine and IBS. While this sensitizing response is generally considered to reside in the central nervous system, it may be possible that the initiation resides in the enteric nervous system as well. What appears to link migraine, IBS, and CD is a disease model of a genetically sensitive nervous system transformed into one that is hypervigilant, and that over time can often develop disabling and pervasive disease.


Asunto(s)
Enfermedad Celíaca/fisiopatología , Sistema Nervioso Entérico/fisiopatología , Síndrome del Colon Irritable/fisiopatología , Trastornos Migrañosos/fisiopatología , Receptores de Serotonina/metabolismo , Enfermedad Celíaca/complicaciones , Enfermedad Celíaca/epidemiología , Enfermedad Celíaca/metabolismo , Comorbilidad , Dieta Sin Gluten , Femenino , Humanos , Síndrome del Colon Irritable/complicaciones , Síndrome del Colon Irritable/epidemiología , Síndrome del Colon Irritable/metabolismo , Masculino , Trastornos Migrañosos/epidemiología , Trastornos Migrañosos/etiología , Trastornos Migrañosos/metabolismo
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